Ratio Of Essential Amino Acids Research Articles

Safflower protein as a potential plant protein powder: optimization of extraction and spray-drying process parameters and determination of physicochemical and functional properties.

The research about sustainable and alternative plant protein sources has accelerated with the increasing need for protein. Safflower meal has a potential to be used in protein production due to its high protein content. This research aimed to produce an alternative plant-based protein powder using safflower meal. Both extraction and spray-drying parameters of safflower protein powder production were optimized using response surface methodology to achieve maximum yield. Moreover, the physicochemical and functional properties of safflower protein were determined and compared with those of commercial protein powders (soy, sunflower, pea, fava bean, and rice). The optimum extraction conditions were found to be 33.06:1 mL-1 g solvent-to-meal ratio, pH 11.00, 23.34 °C extraction temperature, and 30.86 min extraction time, which were achieved with a protein yield response of 75.21%. The highest powder yield (51.28%) was recorded for drying conditions of inlet air temperature of 160.11 °C, aspiration rate of 54.17 m3 h-1, and feed flow rate of 16.01 mL min-1. According to the amino acid profile of safflower protein, the glutamic acid content (14 475 mg (100 g)-1) was highest, while the methionine content (96 mg (100 g)-1) was lowest. Moreover, safflower protein can be regarded as a high-quality protein due to its high essential amino acid ratio (41.55%). The experiments showed that safflower protein had high solubility and good foam and emulsifying properties. Safflower protein could be a nutritional and functional protein source for the food industry. © 2024 Society of Chemical Industry.

Nutritional compositions of native mudskipper (Apocryptes bato) fish influenced by sex: A first report on nutritional profiling of mudskipper in Bangladesh

Native mudskipper (Apocryptes bato) is a freshwater fish species found in the riverine coastal area of Bangladesh. However, nutritional compositions of this fish are still unknown. Thus, as pioneer report, the study aims to determine the chemical compositions, minerals content, amino acids and fatty acids profiles of male and female native mudskipper collected from the Payra River in Bangladesh. The results revealed that female mudskipper had significantly (p < 0.05) higher protein, lipid, ash and energy content in comparison to male mudskipper. The total essential amino acid (EAA) ratio in male (299.59 ± 3.90 mg/g) was observed to be significantly higher (p < 0.05) in contrast to female (250.86 2.04 mg/g) that maintains the FAO/WHO minimum guidance about 40 % for both sexes. With respect to fatty acids content, female were significantly (p < 0.05) higher in eicosapentaenoic acid (EPA; 8.54 %) and docosahexaenoic acid (DHA; 4.89 %) than in male of EPA (6.31 %) and DHA (3.60 %), respectively. However, male had significantly (p < 0.05) higher atherogenic (AI) and thrombogenic (TI) index in comparison to female. The lipid indices (p <0.05) HH, HPI, FLQ and ω-3/ω-6 ratio showed higher 1.14, 1.40, 15.04 and 3.76 for female that was little lower for the male 1.05, 1.21, 11.11 and 3.41, respectively. Female had significantly (p < 0.05) higher mineral levels than male. The study summarize that both male and female species are nutrient enriched including higher minerals, essential amino acids and lipid quality indices. Thus, it could be concluded that nutritionally both male and female mudskipper could be benefited for the human health.

Nutritional value evaluation of wild edible mushroom (Helvella leucopus) from western China

Helvella leucopus, a wild mushroom species, is considered a valuable food by local residents. In the present work, the nutritional value of H. leucopus was evaluated against some commonly cultivated edible and medicinal fungi as controls. H. leucopus showed significantly higher crude protein content. The amino acid composition of H. leucopus met the FAO/WHO ideal protein standard, with the highest ratio of essential amino acid to total amino acid (EAA/TAA) reaching 58.27%. H. leucopus showed the highest correlation with Ganoderma lucidum. The contents of flavour amino acid (FAA) and medicinal amino acid (MAA) in H. leucopus were significantly higher than those in the controls, and a high ratio of branched-chain amino acid to aromatic amino acid (BCAA/AAA) was observed in H. leucopus. The EAA composition of H. leucopus was 54.74%, 1.56- and 1.10-fold higher than that of the FAO/WHO model and the egg model, respectively. On the basis of the amino acid score, nutrition index, and other indices, H. leucopus could be a good protein source rich in amino acids, particularly in EAA and MAA. Therefore, this mushroom species is worthy of further investigation and utilisation, with huge market potential.

Effect of illite pretreatment on germinated Brown rice with Special Reference to amino acids, antioxidants, texture, and mineral elements

The pretreatment process of various foods has been reported to improve their nutritional properties. The soaking of brown rice improves the texture and nutrients, which are crucial for cooking and maintaining its high functional value. Illite, a clay mineral, has recently been discovered to improve the nutritional value of seeds. Based on these findings, we soaked brown rice with different concentrations of illite solution for different durations and allowed the germination to perform analyses. Soaking the brown rice for 6 h with a germination period of 48 h was determined to be the optimal condition because of its higher sprout length. In addition, this optimal condition had improved textural characteristics such as reduced hardness, gumminess, chewiness, and cohesiveness, and it also had increased adhesiveness and stabilized resilience and springiness. The treatment solutions were free from heavy metal contaminants, whereas the mineral contents such as K, Ca, Fe, Mg, and Na were significantly increased with the increase in illite concentration. Moreover, our results showed that illite treatment could preserve the color appearance and seed germination. The ratio of essential amino acids to non-essential amino acids and antioxidants (phenolic contentγ-oryzanol, and flavonoid) of germinated brown rice was considerably increased with illite treatment. In germinated brown rice, an increase in DPPH and superoxide dismutase levels, a slight decrease in flavonoids, and no difference in polyphenol content were observed. These findings suggest that pre-soaking brown rice seeds with the appropriate concentration of illite could enhance their nutritional properties, which might attract consumers' interest to include this in their daily diet.

Meat‐reduced sausage substituted with germinated mung bean flour: proximate composition, physicochemical properties, and sensory acceptability

SummaryThe effects of substituting meat with germinated mung bean flour (GMF) was evaluated as a possible way to reduce the meat content of sausages. Replacement ratios of 10%, 15%, 20%, and 25% were used and the proximate composition, amino acid profile, physicochemical properties (cooking yield and emulsion stability, instrumental texture, and colour), microstructure (by scanning electron microscopy), and overall liking of the sausage products were evaluated. The results showed that elevating the meat substitution ratio from 0% to 25% using GMF increased the protein, carbohydrate, and ash content by 1.14, 2.49, and 1.16 times, while reducing moisture and fat content by 1.16 and 1.2 times. Simultaneously, the total phenolic content (TPC) increased by 46%, accompanied by a 20% rise in antioxidant capacity. Incorporating GMF into the meat‐reduced sausages not only increased the amount of total amino acid and ratio of essential amino acid (EAA) but also enhanced their emulsion stability and cooking yield. The 10%–15% meat substitute samples had the closest colour and textural characteristics to the control and were accepted by the consumers.

The free amino acid profiling of milk- and cereal-based Kyrgyz ethnic fermented beverages and their contribution to taste formation

The present study aimed to determine the content of 18 free amino acids (FAA), including 10 essential amino acids, in traditional fermented beverages and their umami, sweet and bitter taste potential. The FAAs of traditional dairy and cereal-based fermented beverages were measured using high-performance liquid chromatography (HPLC) with a diode array detector and derivatization with diethyl ethoxymethylenemalonate (DEEMM). FAA content and taste attributes with a focus on umami, sweet and bitter were presented for koumiss, ayran, carbonated ayran, boza, boza with sea buckthorn, and maksym. The ratio of free essential amino acids (EFAA) to nonessential (NEFAA) was in the range of 0.41-1.12 except for ayran (0.28), indicating that each type of beverage has a rich source of their respective essential FAA profile. FAA represented 24.68% of the total protein, with the highest value for koumiss. The respective taste property contribution of bitter FAAs was high in koumiss (51%) and carbonated ayran (56%), whereas sweet-tasting FAAs were dominant in jarma (52%). The distribution of taste-active amino acids in the formation of the corresponding tastes was distinct.

“Exotic” seeds from Southern Africa as potential Novel Foods? – Chemical composition of manketti nuts (Schinziophyton rautanenii) and ushivi beans (Guibourtia coleosperma)

Various species of Southern African plants and their edible seeds have gained huge importance due to positive health aspects, and there is increasing interest to introduce such seeds as Novel Food on the international market. Especially the seeds of Schinziophyton rautanenii (manketti) and Guibourtia coleosperma (ushivi) could have great potential as a food and food ingredient. Hence, extensive analyses on the chemical composition of manketti nuts and ushivi beans including the analysis of total solids, protein and fat content, soluble carbohydrates, ash, total and free amino acids, biogenic amines and polyamines, fatty acid profile as well as the content of certain B-vitamins and tocopherols were performed. Results obtained showed a valuable nutritional composition, e.g., a true protein content of 22.6% with a ratio of essential amino acids to total amino acid composition of 48% in manketti nuts, while ushivi beans had a true protein content of 8.2% with a similar ratio of essential to total amino acids (45%). Lipid content was 54.1% in manketti nuts, ushivi beans had a value of 7.7%. In both, linoleic acid was the most abundant. Furthermore, ushivi beans had high amounts of vitamin B1 and B2.

Amino Acid Composition of Cow's Milk of the North Caucasus Black-and-White Breed

The study of the amino acid composition of dairy raw materials, as shown in numerous studies of domestic and foreign authors, is relevant for conducting breeding work on genetic improvement of dairy, optimizing the system of raising animals of various sex and age groups, including lactating cows to prolong the productive longevity period. The purpose of the research was to study the amino acid composition of the milk of cows of the black-and-white Holsteinized breed, considering genotypic, age-related aspects, as well as with an increase in cow milk protein content. Studies on the composition of amino acids in milk were carried out on cows of a black-and-white breed of a pedigree breeding unit of the Stavropol Territory, the Russian Federation. The obtained results showed that the amino acid content in the black-and-white cow milk in the conditions of the North Caucasus corresponds to the parameters characteristic of the black-and-white Holsteinized breed, while the ratio of essential and interchangeable amino acids, considering age and genetic factors, varies in the range of 0.945-0.951, which is typical for high-quality milk. It was also found that in the process of increasing the protein content of cows by 0.2 abs. percentage from a protein level of 3.10% to 3.30%, a more intensive increase in essential amino acids in relation to interchangeable amino acids is observed, while the ratio of essential to interchangeable amino acids statistically significantly (p&lt;0.05) increased by 1.66%, which is of particular importance for planning measures for the genetic improvement of protein content herds of black-and-white cattle.

Nutritional and functional properties of protein hydrolysate from Tra fish by-products

The nutritional and functional properties, molecular weight distribution of protein hydrolysate from Tra fish by-products were studied. The protein hydrolysate was produced by enzymatic hydrolysis of Tra fish by-products with Protamex 0,5% at the temperature of 50 oC in 6 h. The study results showed that the Tra fish by-products protein hydrolysate had a moisture content of 6,7%, protein content of 65.8%, lipid content of 1,6% and ash content of 9,5 %. The protein hydrolysate had a total amino acid content of 52,81 g/100g of protein and essential amino acid content of 16,25 g/100g of protein. The ratio of essential amino acids to total amino acids was 30,76%. The protein hydrolysate was rich in glycine, glutamic, proline, alanine, aspartic and leucine. The most of peptides (68,25%) in Tra fish by-products protein hydrolysate had a molecular weight between 360 Da and 2.500 Da. The protein hydrolysate had solubility in the range of 90,3% - 98,2%. The solubility of protein hydrolysate was the lowest value at pH 4 and the highest value at pH 10. The foaming capacity of protein hydrolysate ranged from 19,5% to 27,8%. The emulsifying capacity of protein hydrolysate was 12,8 – 17,3 mL/g. The protein hydrolysate of Tra fish by-products possesses high nutritional value and good functional properties. The study results suggested that the protein hydrolysate from Tra fish by-products could be used as a promising food ingredient and protein source in food systems. ® 2023 Journal of Science and Technology - NTTU

High-pressure homogenization combined with alcohol treatment is effective in improving the sensory and techno-functional characteristics of Chlorella pyrenoidosa

Chlorella pyrenoidosa (CP) is a microalga that has been used as a sustainable protein and food source. However, its green color from chlorophyll and low processability have limited its broad application in food. This study aimed to evaluate the effectiveness of high-pressure homogenization (HPH) in conjunction with alcohol treatment in removing chlorophyll from CP and its impact on the quality and techno-functionality of the resulting decolorized CP meal. The method was found to be efficient, eco-friendly, and allowed easy recovery of CP components and solvents. It removed chlorophyll effectively and increased CP whiteness from 43.5 ± 1.26 to 86.6 ± 0.55. The combination processing strategy also significantly (p < 0.05) improved the protein quality (e.g., essential amino acid ratio) and functionality (e.g., foaming, emulsification, and gelation) of CP. The results of morphological and electrophoretic analyses indicated that the aggregation behavior of CP molecules was altered in the decolorized sample. Thermochemical and infrared analyses revealed that the decolorization processing reduced CP's heating enthalpy and disrupted hydrophilic β-turns on its globulin surface, causing more random coils. These findings suggest that HPH combined with alcohol treatment can enhance CP sensory characteristics and functionality, which would facilitate its application in the food industry.

Amino acid composition of proteins of hulled and naked oats

The expansion of the production of products with specified functional indicators (cereals, bakery products, pasta, desserts, muesli, yogurts) and feed with a certain amino acid composition is the main task of the food industry and the feed industry, and naked oats have firmly occupied their own niche in these areas of processing. The purpose of the research is to establish the amino acid composition of oat proteins of the hulled oat variety Konkur and naked varieties Bekas and Baget, to assess the balance of essential amino acids in oat proteins relative to the «reference protein» (amino acid scale according to FAO / WHO data) in order to use grain as an additive in food and feed to increase the proportion of essential amino acids in them. The research was carried out during 2018-2022 at the experimental base of the Samara Research Institute of Agriculture. Grain samples of the varieties of filmy and naked oats Konkur, Bekas and Baget were used as experimental material. It was found that the highest proportion of essential amino acids was observed in varieties of naked oats 39,9-41,0 g/kg. The sum of critical amino acids (lysine, methionine, tryptophan) in naked oat varieties was 9,4-9,6 g/kg, which is 1,1-1,3 g/kg higher than in the filmy variety Konkur. According to studies, 1 g of Konkur variety protein contains 249,7 mg of essential amino acids, proteins of naked oat variety Bekas - 268,4 mg and Baget variety - 262,9 mg, which corresponds to 69,4 %, 74,6 % and 73,0 % relative to FAO/WHO recommended standards. The excess of some essential amino acids in naked oat varieties (amino acid score over 100 %) contributed to the imbalance in the ratio of essential amino acids to the «reference» values, while increasing the coefficient of difference in amino acid scores (KRAS protein of Konkur variety was 24,2 %, Bekas variety 33,9 %, varieties Baget 35,5 %), thereby contributing to a decrease in the biological value of the proteins of the varieties Bekas and Baget in relation to the protein of the filmy variety Konkur. Grain of naked oats with a high content of essential amino acids should be used as an ingredient in the production of food and feed with high nutritional value.

Nutritional composition assessment and antimicrobial activity of Catostylus perezi, jellyfish blooms along the coast of Pakistan: an awareness to avoid food neophobia in Pakistan

This study highlighted the nutritional importance of Catostylus perezi (an edible jellyfish) in Pakistan; a society where a large proportion of the population suffers from malnutrition, while C. perezi, a blessing of the sea, is wasted or exported. In the present study, the amino acid and fatty acid profiles of the oral arms and umbrella of C. perezi were determined by HPLC. The total amino acid concentration (ΣAA) in the oral arms was 151.19 mg/100g, while in the umbrella it was 100.17 mg/100g. The ratio of total essential amino acids to total non-essential amino acids (TEAA/TNEAA) was 0.72 in the oral arms, while it was 0.70 in the umbrella. Higher amount of ω-3 with lower ratio of ω-6/ω-3 in oral arms (0.52), rather umbrella (ω-6/ω-3 ratio; 0.62). The antimicrobial activity, MIC, MBC, and MFC of the whole body of the edible jellyfish were determined. On the basis of polarity, different solvents were used, e.g. water, methanol, dichloromethane, chloroform, and n-hexane. Among all the extracts, the water extract gave the highest ZOI against C. xerosis (29 mm), while the n-hexane extract gave the lowest ZOI against S. aureus (MRSA) ATCC 33591 (8.20 mm). The water extract of C. perezi had high potential against C. xerosis with the highest AMI and PAI (1.53 and 153, respectively), while the same extract had the highest TAI against E. coli (81.43 mL/g). For fungi/yeast, the methanolic extract had the highest ZOI (29.70 mm) against S. cerevisiae and the lowest MIC/MFC (2.40 µg/mL) against the same pathogen. The n-Hexane extract gave the lowest ZOI (11.10 mm) against P. variotii and the highest MIC/MFC (31.60 µg/mL) against Penicillium sp. Atomic force microscopy (AFM) was used to analyse the disintegrating effect of the extracts (with the highest antimicrobial effect) on the cells of selected Gram-positive, Gram-negative and yeast species. The amino acid and fatty acid profiles and antimicrobial assessment showed that C. perezi has great nutritional importance, so the use of C. perezi as food is highly recommended for the Pakistani community.

Сезонные изменения биологической ценности белков молока ослиц киргизской породы

Due to its protein component, donkey’s milk is a multifunctional product with a wide range of beneficial physiological properties. It is known for its antioxidant, anti-inflammatory, rejuvenating, antimicrobial, and antitumor effects. However, the milk of Kyrgyz donkeys has not received proper scientific attention in this respect. This study analyzed the seasonal amino acid profile and biological value of milk obtained from Kyrgyz donkeys.&#x0D; The donkeys belonged to the Kyrgyz breed and inhabited the highlands of the Chui Region, Republic of Kyrgyzstan. The sampling took place in April, July, and September. The amino acid composition of milk proteins was determined by capillary electrophoresis. The biological value of proteins was assessed by amino acid score, index of essential amino acids (Auxerre index), utility ratio of essential amino acids, and utility ratio of amino acid composition.&#x0D; The analysis revealed 18 amino acids, including eight essential ones. The total content of amino acids in the spring samples was 1840.07 mg/100 g. In the summer samples, this value peaked at 2037 mg/100 g; in autumn, it dropped to 1264.35 mg/100 g. The changes could be explained by the seasonal differences in the diet. The ratio of essential to non-essential amino acids approached 1:1. The milk also proved to contain arginine, which is an essential amino acid for a juvenile organism. In the spring samples, its content was 2.5 times as big as in the autumn ones. Leucine and isoleucine were responsible for 1/3 of the essential amino acids (322.60 ± 19.35 mg/100 g). The summer samples demonstrated the maximal content of some other essential amino acids, except for valine and tryptophan, which appeared to be the limiting essential amino acids for donkey’s milk in the autumn period. Total essential amino acids in the spring, summer, and autumn samples amounted to 54.24, 59.26, and 34.77 g/100 g, respectively, which exceeded the value for the reference protein (27.46 g/100 g).&#x0D; Kyrgyz donkey’s milk proteins were of high biological value, regardless of the season, which means that donkey’s milk can become part of new functional products.

The nutritional characteristic of spotted seabass (Lateolabrax maculatus) flesh

Spotted seabass (Lateolabrax maculatus) is a popular food fish in Asian countries. Not only does the fish tasted well, but it is also widely utilized as nutraceuticals. However, the knowledge about the composition of the fish is lack. In this work, the proximate composition of spotted seabass flesh was determined. The content of proximate composition (moisture, proteins, fat, and ash) of spotted seabass flesh was fell within the range of other reported fish species, while it was a high-quality food fish with low oil-very high protein. The ratio of essential amino acids (EAAs) to nonessential amino acids (NEAAs) was 0.74, and the amount of EAAs accounted for approximately 42.34% of the total amino acids. Unsaturated fatty acids composed the majority of the fatty acid components, with linoleic acid was the predominate one. The content of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were abundant in spotted seabass flesh. The proximate composition of the dorsal, ventral, lateral, and tail flesh was similar, except for the ventral flesh exhibited a higher content of fatty acids and lower content of moisture. Our research will be helpful for the general population to know the nutritional traits of spotted seabass.

On the question of the amino acid composition of pork with quality defects

The article presents the results of determining the amino acid composition of pork with quality defects, such as PSE, DFD, RSE, RFN and PFN. Meat is one of the traditional sources of high-grade protein, the nutritional and biological value of which depends on the ratio of essential and non-essential amino acids that make up these proteins. The nutritional value and amino acid composition of meat proteins are influenced by various factors, such as the type of animal and breed, gender and age, feeding, storage conditions and others. As part of the implementation of the Food Security Doctrine of the Russian Federation, much attention is paid to improving the quality and rational use of meat and other slaughter products, including those with quality defects such as PSE and DFD. In addition to defects PSE (pale, soft, exudative) and DFD (dark, hard, dry) for pork, there are three more categories: PFN — pale, hard, non-exudative (pH 5.58); RSE — red, soft, exudative (pH 5.67); RFN — red, hard, nonexudative (pH 5.71). The purpose of the research was to evaluate the amino acid composition of pork with quality defects. The research was carried out in the conditions of the educational and research center for the examination of food and animal feed of the St. Petersburg State University of Veterinary Medicine in the period 2021-2022. The materials for the study were 66 samples of pork of various quality categories (11 samples of each category). For the tests, point samples were taken from different muscle groups, then a combined sample was made and sample preparation was carried out according to the M method-04-94-2021 "Determination of amino acids in food products". The amino acid composition of the studied samples was determined according to the M method-04-94-2021 "Determination of amino acids in food products" on the device "Kapel-105M" (GC "LUMEX"), with an autosampler and an automatically switched polarity. As a result of the conducted research, it was found that the content of interchangeable and essential amino acids in pork of different quality categories depended on the type of amino acids and the quality category of pork. It should be noted that information about the amino acid composition of pork with quality defects should be taken into account in the production of meat products at processing plants.

Conditions for making plant dispersions based on nature-like technologies

An objective of this study was to examine the possible use of sprouted grains of domestically selected legumes to produce dairy alternative products. The paper presents the results of a comprehensive assessment of the food properties of ‘Chishminskii 95’, ‘Chishminskii 229’, ‘Pamiati Hangildina’, ‘Iuldash’ pea varieties and ‘Nerussa’, ‘Lukeria’, ‘Omichka’ bean varieties of Russian selection. The work investigated the water absorption kinetics under different temperature conditions and established germination patterns for a model medium (drinking water treated with an electromagnetic field) being as follows: germination temperature is 18 ± 2 °C; the soaking period lasts from 5 to 8 hours (depending on the variety); the germination time from 0.54 - 0.62 to 0.70 - 0.81 days (depending on the variety). The work analyses their microstructure and changes in the germination process. The proteolytic activity of bean trypsin before and after germination has been proved to be lower than that of peas. At the same time, the proteolytic activity of trypsin after pea and bean grain germination increased in all samples. The grain digestibility as a result of germination has increased; the ratio of essential and non-essential amino acids has changed in favor of the former; the fractional composition of protein has changed to higher content of albumin and globulin and lower level of glutelin. The results of this study indicate that the most suitable varieties to produce vegetable milk are ‘Omichka’, ‘Lukeria’ beans and ‘Pamiati Hangildina’ peas.

Comparative Study on Nutritional Characteristics and Volatile Flavor Substances of Yak Milk in Different Regions of Gannan.

This study aimed to investigate the nutritional properties of yak milk in various areas of Gannan. The milk composition analyzer, automatic amino acid analyzer, and flavor analyzer were used to detect the conventional nutrients, amino acids, and volatile flavor substances of 249 yak milks in Meiren grassland, Xiahe grassland, and Maqu grassland (hereinafter referred to as Meiren yak, Xiahe yak, and Maqu yak) in the Gannan area. The results showed that the fat content of Meiren yak milk was significantly higher than that of Maqu yak and Xiahe yak (p < 0.05). The protein content of Meiren yak milk was significantly higher than that of Xiahe yak (p < 0.05), but not significantly different from that of Maqu yak (p > 0.05). The casein content in the milk of Maqu yak was significantly higher than that of Meiren yak and Xiahe yak (p < 0.05). There was no significant difference in the lactose content of yak milk in the three regions (p > 0.05). The content of glutamic acid in the milk of Meiren yak, Xiahe yak, and Maqu yak was noticeably high, which was 1.03 g/100 g, 1.07 g/100 g, and 1.10 g/100 g, respectively. The total amino acid (TAA) content was 4.78 g/100 g, 4.87 g/100 g, and 5.0 g/100 g, respectively. The ratios of essential amino acids (EAA) and total amino acids (TAA) in the milk of Meiren yak, Xiahe yak, and Maqu yak were 42.26%, 41.27%, and 41.39%, respectively, and the ratios of essential amino acids (EAA) and nonessential amino acids (NEAA) were 73.19%, 70.28%, and 70.61%, respectively. In the yak milk samples collected from three different regions, a total of 34 volatile flavor compounds were detected, including 10 aldehydes, five esters, six ketones, four alcohols, two acids, and seven others. The main flavor substances qualitatively obtained from Meiren yak milk were ethyl acetate, n-valeraldehyde, acetic acid, heptanal, and n-hexanal. Xiahe yak milk mainly contains ethyl acetate, isoamyl alcohol, n-valeraldehyde, heptanal, and ethyl butyrate. Maqu yak milk mainly contains ethyl acetate, n-valeraldehyde, isoamyl alcohol, heptanal, ethyl butyrate, and n-hexanal. Principal component analysis showed that the flavor difference between Xiahe yak and Maqu yak was small, while the flavor difference between Xiahe yak, Maqu yak, and Meiren yak was large. The findings of this research can serve as a foundation for the future advancement and application of yak milk.

Metabolic profiling of COVID-19 severity and mortality: A targeted metabolomics approach

Abstract The analysis of metabolites in response to SARS-CoV-2 infection provides a snapshot of the endogenous host metabolism and its role in shaping the interaction with SARS-CoV-2. In this study, using a targeted metabolomics approach, the metabolic signatures of severity and mortality were studied in COVID-19 patients. Our analysis revealed survival and severity-associated shifts in the metabolome of COVID-19 patients, where amino acids, particularly tryptophan and arginine, and fatty acid metabolism were altered in severe patients as compared to mild and asymptomatic cases. Herein, we also report alterations in the sums and ratios of several essential amino acids as well as kynurenine to tryptophan ratio, which is an indicator of indoleamine-2,3-dioxygenase (IDO) activity. Our findings suggest that metabolites of creatine including symmetric dimethylarginine, asymmetric dimethylarginine, and 1-methylhistidine can be used as biomarkers to identify patients at risk of poor outcomes in COVID-19, and that lower levels of these metabolites are associated with higher survival probabilities. Additionally, elevated levels of short chain acylcarnitines and carnitine palmitoyltransferase 1 and 2 enzymes indicators have been observed in critically ill COVID-19 patients, indicating their potential usefulness as predictors of hospital mortality and poor survival outcome, likely due to increased demand for energy, inflammation, and mitochondrial dysfunction. The metabolome analysis of COVID-19 patients can improve our understanding of disease severity by providing insight into the relationship between metabolites and disease progression, which can lead to the development of potential therapeutics and clinical risk models. This work was supported by Emergency Response Grant ID: 252

Technology of protein isolate from peas (Pisum sativum var. arvense)

The object of research is pea (Pisum sativum var. arvense) and pea protein isolate. The chemical composition of pea (Pisum sativum var. arvense) was studied to determine its potential as a new raw material for obtaining protein isolate by pH-shifting treatment. The obtained results confirm the effectiveness of using peas to obtain protein isolate for use in the food industry instead of soy protein isolate. Peas are low in lipids (1.61 % on dry matter), high in crude protein (19.21 % on dry matter), ash (3.41 % on dry matter) and minerals (Se, Fe, Zn, Mn, Cu, Mg, P). The ratio of essential amino acids to replaceable amino acids (0.78), which is higher than the amount recommended by the World Health Organization. Vegetable protein is an alternative to animal protein in the food industry. Protein isolate from peas was obtained by pH-shifting treatment and its chemical composition and functional properties were determined. After pH-shifting treatment, the chemical composition of protein and mineral substances did not show significant changes. The protein content of pea protein isolate was 82.2 %, and the yield of pea protein isolate was 5.6 %. To confirm the functional properties of pea protein isolate, the indicators of moisture-holding capacity (1.05 ml/g) and fat-holding capacity (0.82 ml/g) were investigated. Peas and protein isolate from it showed high functional properties and high-quality chemical composition of proteins and minerals for use in the technology of sausage products, which should be the focus of further research.

Evaluation of Meat Quality of Local Pigeon Varieties in China.

To evaluate the germplasm characteristics and nutritional value of Chinese native pigeon varieties, this study analyzed the nutrient composition of the meat of four Chinese native pigeon varieties and then compared them with those of the White King pigeon, which is the most commonly used in China. A total of 150 pigeons aged 28 d (squabs) of 5 breeds including Taihu pigeon, Shiqi pigeon, Ta-rim pigeon, Boot pigeon, and White King pigeon were selected for slaughter. The basic meat quality parameters and contents of conventional nutritional compositions, inosine acid, amino acids, and fatty acids were measured. The results showed that there were significant differences in flesh color (L*, b*), pH, and water loss rate of different breeds of suckling pigeons (p < 0.05). Compared with White King pigeons, four local breeds had dark breast meat and a low water loss rate. The protein contents of Taihu, Tarim, and Shiqi suckling pigeons were significantly higher than those of White King pigeons (p < 0.05). Taihu pigeons had the highest protein content, reaching 22.72%. The inosinic acid content of Tarim pigeons was the highest (1.31 mg/g) and was significantly higher than that of Shiqi pigeons, Boot pigeons, and White King pigeons (p < 0.05). There was no significant difference in the content of amino acids, the ratio of essential amino acids, and the ratio of umami amino acids in the meat of different breeds of pigeons (p > 0.05). The percentage of saturated fatty acids (SFAs) in the breast muscle of local breeding pigeons was significantly lower than that of White King pigeons (p < 0.05), and the percentages of lauric acid, palmitic acid, eicosanoic acid, and behenic acid in SFAs reached significant levels (p < 0.05). The content of eicosapentaenoic acid (EPA) in the meat of Taihu pigeons was significantly higher than that in other breeds. In conclusion, compared with the White King pigeon, the meat of local breed pigeons (Taihu pigeon, Shiqi pigeon, Tarim pigeon, and Boot pigeon) had dark flesh, good water retention, high protein and inosine contents, a high proportion of essential amino acids, and a low saturated fatty acid ratio. In addition, Taihu pigeons had the highest protein content (22.72%), monounsaturated fatty acids (44.58%), and EPA (0.47%) compared to other breeds.